# from https://github.com/magic-sph/magic/blob/master/cmake/FindSSE.cmake
# Check if SSE/AVX instructions are available on the machine where
# the project is compiled.

# check which architecture first, only for x86 check SSE
if(${CMAKE_SYSTEM_PROCESSOR} MATCHES "x86_64")
    IF(CMAKE_SYSTEM_NAME MATCHES "Linux")
        EXEC_PROGRAM(cat ARGS "/proc/cpuinfo" OUTPUT_VARIABLE CPUINFO)

        STRING(REGEX REPLACE "^.*(sse2).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "sse2" "${SSE_THERE}" SSE2_TRUE)
        IF (SSE2_TRUE)
            set(SSE2_FOUND true CACHE BOOL "SSE2 available on host")
        ELSE (SSE2_TRUE)
            set(SSE2_FOUND false CACHE BOOL "SSE2 available on host")
        ENDIF (SSE2_TRUE)

        # /proc/cpuinfo apparently omits sse3 :(
        STRING(REGEX REPLACE "^.*[^s](sse3).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "sse3" "${SSE_THERE}" SSE3_TRUE)
        IF (NOT SSE3_TRUE)
            STRING(REGEX REPLACE "^.*(T2300).*$" "\\1" SSE_THERE ${CPUINFO})
            STRING(COMPARE EQUAL "T2300" "${SSE_THERE}" SSE3_TRUE)
        ENDIF (NOT SSE3_TRUE)

        STRING(REGEX REPLACE "^.*(ssse3).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "ssse3" "${SSE_THERE}" SSSE3_TRUE)
        IF (SSE3_TRUE OR SSSE3_TRUE)
            set(SSE3_FOUND true CACHE BOOL "SSE3 available on host")
        ELSE (SSE3_TRUE OR SSSE3_TRUE)
            set(SSE3_FOUND false CACHE BOOL "SSE3 available on host")
        ENDIF (SSE3_TRUE OR SSSE3_TRUE)
        IF (SSSE3_TRUE)
            set(SSSE3_FOUND true CACHE BOOL "SSSE3 available on host")
        ELSE (SSSE3_TRUE)
            set(SSSE3_FOUND false CACHE BOOL "SSSE3 available on host")
        ENDIF (SSSE3_TRUE)

        STRING(REGEX REPLACE "^.*(sse4_1).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "sse4_1" "${SSE_THERE}" SSE41_TRUE)
        IF (SSE41_TRUE)
            set(SSE4_1_FOUND true CACHE BOOL "SSE4.1 available on host")
        ELSE (SSE41_TRUE)
            set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
        ENDIF (SSE41_TRUE)

        STRING(REGEX REPLACE "^.*(avx).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "avx" "${SSE_THERE}" AVX_TRUE)
        IF (AVX_TRUE)
            set(AVX_FOUND true CACHE BOOL "AVX available on host")
        ELSE (AVX_TRUE)
            set(AVX_FOUND false CACHE BOOL "AVX available on host")
        ENDIF (AVX_TRUE)

        STRING(REGEX REPLACE "^.*(avx2).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "avx2" "${SSE_THERE}" AVX2_TRUE)
        IF (AVX2_TRUE)
            set(AVX2_FOUND true CACHE BOOL "AVX2 available on host")
        ELSE (AVX2_TRUE)
            set(AVX2_FOUND false CACHE BOOL "AVX2 available on host")
        ENDIF (AVX2_TRUE)

    ELSEIF(CMAKE_SYSTEM_NAME MATCHES "Darwin")
        EXEC_PROGRAM("/usr/sbin/sysctl -n machdep.cpu.features" OUTPUT_VARIABLE
                CPUINFO)

        STRING(REGEX REPLACE "^.*[^S](SSE2).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "SSE2" "${SSE_THERE}" SSE2_TRUE)
        IF (SSE2_TRUE)
            set(SSE2_FOUND true CACHE BOOL "SSE2 available on host")
        ELSE (SSE2_TRUE)
            set(SSE2_FOUND false CACHE BOOL "SSE2 available on host")
        ENDIF (SSE2_TRUE)

        STRING(REGEX REPLACE "^.*[^S](SSE3).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "SSE3" "${SSE_THERE}" SSE3_TRUE)
        IF (SSE3_TRUE)
            set(SSE3_FOUND true CACHE BOOL "SSE3 available on host")
        ELSE (SSE3_TRUE)
            set(SSE3_FOUND false CACHE BOOL "SSE3 available on host")
        ENDIF (SSE3_TRUE)

        STRING(REGEX REPLACE "^.*(SSSE3).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "SSSE3" "${SSE_THERE}" SSSE3_TRUE)
        IF (SSSE3_TRUE)
            set(SSSE3_FOUND true CACHE BOOL "SSSE3 available on host")
        ELSE (SSSE3_TRUE)
            set(SSSE3_FOUND false CACHE BOOL "SSSE3 available on host")
        ENDIF (SSSE3_TRUE)

        STRING(REGEX REPLACE "^.*(SSE4.1).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "SSE4.1" "${SSE_THERE}" SSE41_TRUE)
        IF (SSE41_TRUE)
            set(SSE4_1_FOUND true CACHE BOOL "SSE4.1 available on host")
        ELSE (SSE41_TRUE)
            set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
        ENDIF (SSE41_TRUE)

        STRING(REGEX REPLACE "^.*(AVX).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "AVX" "${SSE_THERE}" AVX_TRUE)
        IF (AVX_TRUE)
            set(AVX_FOUND true CACHE BOOL "AVX available on host")
        ELSE (AVX_TRUE)
            set(AVX_FOUND false CACHE BOOL "AVX available on host")
        ENDIF (AVX_TRUE)

        STRING(REGEX REPLACE "^.*(AVX2).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "AVX2" "${SSE_THERE}" AVX2_TRUE)
        IF (AVX2_TRUE)
            set(AVX2_FOUND true CACHE BOOL "AVX2 available on host")
        ELSE (AVX2_TRUE)
            set(AVX2_FOUND false CACHE BOOL "AVX2 available on host")
        ENDIF (AVX2_TRUE)

    ELSEIF(CMAKE_SYSTEM_NAME MATCHES "Windows")
        # TODO
        set(SSE2_FOUND   true  CACHE BOOL "SSE2 available on host")
        set(SSE3_FOUND   false CACHE BOOL "SSE3 available on host")
        set(SSSE3_FOUND  false CACHE BOOL "SSSE3 available on host")
        set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
        set(AVX_FOUND false CACHE BOOL "AVX available on host")
        set(AVX2_FOUND false CACHE BOOL "AVX2 available on host")
    ELSE(CMAKE_SYSTEM_NAME MATCHES "Linux")
        set(SSE2_FOUND   true  CACHE BOOL "SSE2 available on host")
        set(SSE3_FOUND   false CACHE BOOL "SSE3 available on host")
        set(SSSE3_FOUND  false CACHE BOOL "SSSE3 available on host")
        set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
        set(AVX_FOUND false CACHE BOOL "AVX available on host")
        set(AVX2_FOUND false CACHE BOOL "AVX2 available on host")
    ENDIF(CMAKE_SYSTEM_NAME MATCHES "Linux")

else(${CMAKE_SYSTEM_PROCESSOR} MATCHES "aarch64")
    # set to false, only x86 has sse
    set(SSE2_FOUND false CACHE BOOL "SSE2 available on host")
    set(SSE3_FOUND false CACHE BOOL "SSE3 available on host")
    set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
    set(AVX_FOUND false CACHE BOOL "AVX available on host")
    set(AVX2_FOUND false CACHE BOOL "AVX2 available on host")
endif()


if(NOT SSE2_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSE2 on this machine.")
endif(NOT SSE2_FOUND)
if(NOT SSE3_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSE3 on this machine.")
endif(NOT SSE3_FOUND)
if(NOT SSSE3_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSSE3 on this machine.")
endif(NOT SSSE3_FOUND)
if(NOT SSE4_1_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSE4.1 on this machine.")
endif(NOT SSE4_1_FOUND)
if(NOT AVX_FOUND)
    MESSAGE(STATUS "Could not find hardware support for AVX on this machine.")
endif(NOT AVX_FOUND)
if(NOT AVX2_FOUND)
    MESSAGE(STATUS "Could not find hardware support for AVX2 on this machine.")
endif(NOT AVX2_FOUND)

mark_as_advanced(SSE2_FOUND SSE3_FOUND SSSE3_FOUND SSE4_1_FOUND, AVX_FOUND, AVX2_FOUND)